Apparatus for feeding elastic yarn to a circular knitting machine

ABSTRACT

Apparatus for feeding elastic yarn to a circular knitting machine comprising a yarn-feeding unit mounted on a circular arm placed coaxially with the center line of the circular knitting machine, said feeding unit including of a yarn package and a roller contacting the package and being rotated by a circular belt through a driving pulley rotating in concert with the rotation of the circular knitting machine, to unwind the yarn package as it rotates in the same direction as the rotation of the roller.

ll] States atet [72] Inventor AkijlSugiura Osaka-1m, Japan 21 ApplNo. 750,672 [22] Filed .lune25,1968 [45] Patented July/6,1971

[73] Assignee AsahiKaseiKogyoKabushiltiKeisha Osaka-511i, Japan [32] Priority June 27, 1967, Aug. 4, 1967 [33] Japan [31 42/549011 and 42/498112 [54] APPARATUS FOR FEEDING ELASTIC YARN TO A CIRCULAR KNITTING MACHINE 1 Claim, 6 Drawing Figs.

[52] 11.5. C1 66/132 [51] Int. Cl D04b'15/50 {50] Field 01 Search 66/132, 125; 242/65 [56] References Cited UNITED STATES PATENTS 201,629 3/1878 Paul 66/125 784,295 3/1905 Bellamy... 242/65 1,805,122 5/1931 Weinheim 242/65 2,627,738 2/1953 Lawson 66/132 2,290,628 7/1942 Alderfer H 66/132 2,306,660 12/1942 011 11.... 66/132(UX) 2,441,189 5/1943 Eshleman.. 66/132(X) 3,209,558 10/1965 Cargill H 66/132 3,303,671 2/1967 Oliver 66/132 FOREIGN PATENTS 215,484 5/1924 GreatBritain .1 66/125 1,067,038 4/1967 GreatBritain 66/132 OTHER REFERENCES How To Reduce Barre In Knitting Textured Yarn Double Knits by James H. Blore, KNITTED OUTERWEAR TIMES, February 12, 1968, Vol. 37, No. 7. pps. 75 78 necessary. Copy in Group 352, Class 66, subclass 132 (T).

Primary Examiner-- Robert R. Mackey A!t0rney-Whittmore, 1-Iulbert & Belknap ABSTRACT: Apparatus for feeding elastic yarn to a circular knitting machine comprising a yarn-feeding unit mounted on a circular arm placed coaxially'with the center line of the circular knitting machine, said feeding unit including of a yarn package and a roller contacting the package and being rotated by a circular belt through a driving pulley rotating in concert with the rotation of the circular knitting machine, to unwind the yarn package as it rotates in the same direction as the rota tion of the roller.

PATENTEDJIJL-SIQ?! 3,590,601

SHEET 1 [IF 3 INVENTOR AKIJI SUGIURA BY mzam, MM

ATTORNEYS PATENTEDJUL-BIEWI 3,590,601

SHEET 3 [IF 3 Tensi on(g ram) 0 m 6 024681012141618 Time (second) Fig. 6

Tensi0n( r m) o 01 'o" 8 Time (second) INV- OR AKIJI GIURA ATTORNEYS APPARATUS FOR FEEDHNG ELASTIC YARN TO A CIRCULAR KNITTING MACFMNE BACKGROUND OF THE INVENTION 1. Scope of the Invention This invention relates to apparatus for feeding elastic yarn to a circular knitting machine wherein yarn-feeding units are independently dispersed around the circumference of the knitting machine instead of being concentrated in a place or two, thereby insuring the feed of every elastic yarn under uniform conditions of distance, number and angle of the contacts of the elastic yarn with yarn guides from yarn unwinding to the entrance at the knitting needles and at the same time enabling the yarn to be fed positively and uniformly to the knitting needles by contacting the elastic yarn unwound from a package or cheese at each unit with the circumferential edge of a roller rotating inthe same direction as the yarn is to be unwound.

2. Description of the Prior Technique In a conventional apparatus used for feeding elastic yarn,

there has been employed a method wherein the yarn or cheese is brought into contact with oneor two rollers so as to rotate said package for the purpose of feeding yarn after unwinding. There is also proposed another method wherein elastic yarn rising from the package is fed while being clasped under a regular control. However, these conventional feeding methods are not satisfactory for the following reasons: in the conventional yarn feeding methods, yarn is unwound, and fed by concentrating paper tube yarn packages at a place or two near a circular knitting machine, so that in the course where elastic yarn is unwound from the package and is fed to knitting needles, each elastic yarn has its own distance, its own number of times of contact, its own angle of contacting the guide, etc. Resultantly there is difficulty in controlling yarn-feeding tension. Moreover, when the yarn is wound around a bobbin and is stored, the elastic yarn sometimes becomes adhesive. In this way, adhesion which is brought about irregularly in the package will cause sticking among elastic yarns, and there is a defect that, when elastic yarn is unwound from the paper tube, the point of contact of yarn unwinding changes irregularly and the unevenness in unwinding tension, yarn breaking, etc. takes place. Thus, there have been undesirable lateral stripes and unevenness of shrinkage owing to the above-mentioned causes.

SUMMARY OF THE INVENTION A circular arm provided coaxially with a cylinder of a circular knitting machine is fitted with a yarn-feeding unit for unwinding a package such as a cheese wound with elastic yarn and for feeding yarn from said package; said yarn-feeding unit being driven from a pulley through a circular belt in concert with the rotation of said circular knitting machine, said package being pressed and contacted with the roller of the yarn feeding unit and rotated as the roller rotates to thereby unwind the yarn from the package and deliver yarn therefrom to knitting needles. Moreover, yarn is fed to the knitting needles as the yarn is brought into contact with the circumferential edge of said roller in the same direction of rotation.

According to the above-mentioned yarn-feeding method, yarn can be fed under such condition that all of the distances, the number of times of contact and the angle of the contact with the yarn guides are quite the same in every course where elastic yarn is unwound from a plurality of yarn-feeding units so as to be fed to knitting needles. In addition, it is possible to minimize the unevenness of yam-winding tension and also to reduce the breaking of yarn.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a plan view of elastic-yarn-feeding apparatus for a circular knitting machine according to this invention:

FIG. 2 is a section view of the apparatus shown in FIG. 1 taken substantially on the line II-II of FIG. ll;

FIG. 3 is an enlarged partial section view of the apparatus shown in FIG. ll similar to the extreme left part of FIG. 2;

FIG. 4 is a partial section view of the structure shown in FIG. 3 taken substantially on the line lV-IV of FIG. 3;

FIG. 5 is a graph showing the change of yarn-feeding tension in the course of time using this yarn-feeding apparatus;

FIG. 6 is likewise a graph showing the change of yarn-feeding tension in the course of time using a conventional yarnfeeding method.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIGS. ll, 2, 3 and 4, plural yarn-feeding units, 3, 3', 3", 3" are provided on the circumferential edge of a circular arm 2 provided in an arclike shape at the upper end of the frame 1 of a circular knitting machine. Each yarn-feeding unit has the same construction, so that the explanation will be given only with reference to the yarn-feeding unit 3. The yarn-feeding unit 3 includes a roller support 6 having a pair of arms 4 5, a roller 7 and a yarn package 3 placed adjacent thereto such as a cheese. The roller 7 is supported on the arms 4, 5 by a shaft 9. A pulley ill) for rotating the shaft 9 is provided at its upper end.

Grooves or slits l ll, 12 extending straight toward said shaft 9 are respectively provided on the arms 5, 5. Into said grooves ill, l2 are respectively inserted the upper and lower ends of a bobbin shaft 115 to which a bobbin 13 containing a package such as a cheese is inserted through a bobbin-receiving drum M. A spring 16 and a spring 17 provided respectively on the upper and lower ends of bobbin shaft. 15 are connected with pins lb and 19 provided on the arms 4, 5, so that a package such as a cheese 3 is urged into resilient contact with roller 7.

Pulleys ll), l0, it)", illl are provided respectively on yarn-feeding devices 3, 3', 3", 3" in the same plane, and a driving endless belt 26 is placed around respective pulleys 10, ll), 10'', lll'. Said endless belt 20 is driven by a pulley 22 provided on a driving shaft 21 driven by motive power, not shown in the drawings. Tension is given to the driving endless belt 20 by force of tension rollers 23, 24, 25, 26, 27. Elastic yarn 23 delivered from such a package as a cheese 8 comes into contact with the circumferential edge of the roller 7 adjacent to the package b in the direction of the rotation of the roller and then is guided by yarn guides 29, 30.

The elastic yarn 28 is fed to cylinder needles 35 and dial needles 3b which are positioned in a cylinder 31 and a dial 32 and are alternately protrudable and retractable by the movements of cylinder cam 33 and a dial cam 34, and then the fed yarn is formed into knit fabric 37. Ordinary yarn 38 is delivered from a package, not shown in the drawings, and is gathered together with the elastic yarn at the guide 30, then fed to the cylinder needles 35 and the dial needles 36.

As explained above, the elastic-yarnz-feeding apparatus according to this invention is so operated that each unit is rotated by the driving pulley 22 through the circular belt 20, pulley l0 and roller '7 so that a cheese package 8 is rotated by contacting the package with the roller positively to pull out the yarn. Thus, as compared with the heretofore known package-feeding method, the apparatus according to this invention can disperse the yarn-feeding units independently along the circumferential edge of the circular arm 2 disposed coaxially with the cylinder of the knitting machine. Therefore, all of the distance, the number of times of contact, the angle of contact with the guides, etc. can be kept the same for each yarn package where yarn packages 8 are unwound and yarn is fed to the knitting needles 35, 36. Thus, it is possible to completely remove defects such as difficulty in the control of tension due to the extensibility of elastic: yarn 28.

In addition, as the yarn-feeding units 3, 3', 3", 3" can be dispersed around the circular arm 2, the: extra area required in case of equipping the yarn-feeding devices in concentrated relations is not necessary. Therefore, in case of fitting the apparatus of the present invention to hithertofore-used knitting machines, it is advantageous that the operation and working of the knitting machine can never be hindered.

Furthermore, when the bobbin 13 is unwound and elastic yarn 28 is fed therefrom, there are such advantages as the lessening and adjustment'of the unevenness of unwinding tension, the reduction of the breaking of yarn, etc.

FIG. 5 is a graph showing the change of yarn feeding tension in the course of time when elastic yarn 28 is brought into contact with the roller 7 in the same direction of rotation as the roller 7; FIG. 6 is likewise a graph showing the change of yarnfeeding tension in the course of time when elastic yarn is directly unwound according to the heretofore used method. According to these graphs, the extent of variation of unevenness in yam-feeding tension due to the unevenness of yarn rewinding according'to the heretofore used method is about 4 grams, but according to this invention said extent is reduced to about 2 grams.

As hereinbefore-mentioned, this invention can overcome the defects of the hithertofore-used yarn unwinding apparatus. In addition, according to this invention it is possible to produce cheaply and moreover very efficiently desired elastic knitted fabrics in good quality by unwinding elastic yarn positively and uniformly, so the practical values of this invention are very large.

What I claim as my invention is:

1. Structure for feeding yarn to a circular knitting machine comprising a circular arm having a diameter greater than that of the knitting machine positioned concentrically of and above the knitting machine, a plurality of yam-feeding units secured to the circular arm in equal, angularly spaced-apart, positions around the inner circumference of the circular arm, radially outwardly of the knitting machine, each including a U-shaped yoke having longitudinally slotted leg portions and a connecting portion, said connecting portion being secured to the arm with the slotted leg portions extending radially inwardly of the arm toward the knitting machine, a roller having an axis of rotation parallel to the axis of the knitting machine positioned between the leg portions of each yoke, a roller shaft mounting the roller for rotation and extending through the upper leg portion away from the knitting machine and having a driven pulley secured thereto for rotation therewith, a yarn package having an axis of rotation parallel to and positioned radially outwardly of the knitting machine and radially inwardly of the roller axis, a spindle supporting the yarn package for rotation including a spindle shaft positioned within the slots in the leg portions of the yoke member and spring means connected between the opposite ends of the spindle shaft and the yoke supporting the yarn package in contact with the roller for rotation on rotation of the roller to unwind yarn from the yarn package in the direction of rotation of the roller, guide means for guiding the unwound yarn from the package to the knitting machine through substantially the same path comprising a first guide member positioned adjacent each yarn package at the level of the yarn package and angularly displaced therefrom about the circular arm for receiving yarn unwound from the yarn package and passed around the roller, which guide member is positioned radially outwardly of the knitting machine and radially inwardly of the yarn package and over which guide member the yarn passes downwardly toward the knitting machine, a second guide member positioned below the first guide member immediately adjacent the knitting machine and slightly above and radially outwardly of the knitting machine and radially inwardly of the first guide member under which the yarn is passed to the knitting machine, means for rotating the rollers in accordance with the operation of the knitting machine comprising a drive pulley positioned radially inwardly of the circular arm, means for rotating the drive pulley in synchronisrn with the knitting machine, idler pulleys positioned angularly between the yarn feeding units and immediately adjacent and angularly separated on each side of the drive pulley and a drivebelt passing over each of the idler pulleys and the pulleys secured to the roller shafts radially outwardly thereof with respect to the knitting machine and passing over the drive pulley radially inwardly thereof with respect to the knitting machine. 

1. Structure for feeding yarn to a circular knitting machine comprising a circular arm having a diameter greater than that of the knitting machine positioned concentrically of and above the knitting machine, a plurality of yarn-feeding units secured to the circular arm in equal, angularly spaced-apart, positions around the inner circumference of the circular arm, radially outwardly of the knitting machine, each including a U-shaped yoke having longitudinally slotted leg portions and a connecting portion, said connecting portion being secured to the arm with the slotted leg portions extending radially inwardly of the arm toward the knitting machine, a roller having an axis of rotation parallel to the axis of the knitting machine positioned between the leg portions of each yoke, a roller shaft mounting the roller for rotation and extending through the upper leg portion away from the knitting machine and having a driven pulley secured theReto for rotation therewith, a yarn package having an axis of rotation parallel to and positioned radially outwardly of the knitting machine and radially inwardly of the roller axis, a spindle supporting the yarn package for rotation including a spindle shaft positioned within the slots in the leg portions of the yoke member and spring means connected between the opposite ends of the spindle shaft and the yoke supporting the yarn package in contact with the roller for rotation on rotation of the roller to unwind yarn from the yarn package in the direction of rotation of the roller, guide means for guiding the unwound yarn from the package to the knitting machine through substantially the same path comprising a first guide member positioned adjacent each yarn package at the level of the yarn package and angularly displaced therefrom about the circular arm for receiving yarn unwound from the yarn package and passed around the roller, which guide member is positioned radially outwardly of the knitting machine and radially inwardly of the yarn package and over which guide member the yarn passes downwardly toward the knitting machine, a second guide member positioned below the first guide member immediately adjacent the knitting machine and slightly above and radially outwardly of the knitting machine and radially inwardly of the first guide member under which the yarn is passed to the knitting machine, means for rotating the rollers in accordance with the operation of the knitting machine comprising a drive pulley positioned radially inwardly of the circular arm, means for rotating the drive pulley in synchronism with the knitting machine, idler pulleys positioned angularly between the yarn feeding units and immediately adjacent and angularly separated on each side of the drive pulley and a drivebelt passing over each of the idler pulleys and the pulleys secured to the roller shafts radially outwardly thereof with respect to the knitting machine and passing over the drive pulley radially inwardly thereof with respect to the knitting machine. 